1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #include <linux/blkdev.h> 20 #include <linux/module.h> 21 #include <linux/buffer_head.h> 22 #include <linux/fs.h> 23 #include <linux/pagemap.h> 24 #include <linux/highmem.h> 25 #include <linux/time.h> 26 #include <linux/init.h> 27 #include <linux/seq_file.h> 28 #include <linux/string.h> 29 #include <linux/backing-dev.h> 30 #include <linux/mount.h> 31 #include <linux/mpage.h> 32 #include <linux/swap.h> 33 #include <linux/writeback.h> 34 #include <linux/statfs.h> 35 #include <linux/compat.h> 36 #include <linux/parser.h> 37 #include <linux/ctype.h> 38 #include <linux/namei.h> 39 #include <linux/miscdevice.h> 40 #include <linux/magic.h> 41 #include "compat.h" 42 #include "ctree.h" 43 #include "disk-io.h" 44 #include "transaction.h" 45 #include "btrfs_inode.h" 46 #include "ioctl.h" 47 #include "print-tree.h" 48 #include "xattr.h" 49 #include "volumes.h" 50 #include "version.h" 51 #include "export.h" 52 #include "compression.h" 53 54 static struct super_operations btrfs_super_ops; 55 56 static void btrfs_put_super(struct super_block *sb) 57 { 58 struct btrfs_root *root = btrfs_sb(sb); 59 int ret; 60 61 ret = close_ctree(root); 62 sb->s_fs_info = NULL; 63 } 64 65 enum { 66 Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, 67 Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, 68 Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, 69 Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_err, 70 }; 71 72 static match_table_t tokens = { 73 {Opt_degraded, "degraded"}, 74 {Opt_subvol, "subvol=%s"}, 75 {Opt_device, "device=%s"}, 76 {Opt_nodatasum, "nodatasum"}, 77 {Opt_nodatacow, "nodatacow"}, 78 {Opt_nobarrier, "nobarrier"}, 79 {Opt_max_extent, "max_extent=%s"}, 80 {Opt_max_inline, "max_inline=%s"}, 81 {Opt_alloc_start, "alloc_start=%s"}, 82 {Opt_thread_pool, "thread_pool=%d"}, 83 {Opt_compress, "compress"}, 84 {Opt_ssd, "ssd"}, 85 {Opt_ssd_spread, "ssd_spread"}, 86 {Opt_nossd, "nossd"}, 87 {Opt_noacl, "noacl"}, 88 {Opt_notreelog, "notreelog"}, 89 {Opt_flushoncommit, "flushoncommit"}, 90 {Opt_ratio, "metadata_ratio=%d"}, 91 {Opt_err, NULL}, 92 }; 93 94 u64 btrfs_parse_size(char *str) 95 { 96 u64 res; 97 int mult = 1; 98 char *end; 99 char last; 100 101 res = simple_strtoul(str, &end, 10); 102 103 last = end[0]; 104 if (isalpha(last)) { 105 last = tolower(last); 106 switch (last) { 107 case 'g': 108 mult *= 1024; 109 case 'm': 110 mult *= 1024; 111 case 'k': 112 mult *= 1024; 113 } 114 res = res * mult; 115 } 116 return res; 117 } 118 119 /* 120 * Regular mount options parser. Everything that is needed only when 121 * reading in a new superblock is parsed here. 122 */ 123 int btrfs_parse_options(struct btrfs_root *root, char *options) 124 { 125 struct btrfs_fs_info *info = root->fs_info; 126 substring_t args[MAX_OPT_ARGS]; 127 char *p, *num; 128 int intarg; 129 130 if (!options) 131 return 0; 132 133 /* 134 * strsep changes the string, duplicate it because parse_options 135 * gets called twice 136 */ 137 options = kstrdup(options, GFP_NOFS); 138 if (!options) 139 return -ENOMEM; 140 141 142 while ((p = strsep(&options, ",")) != NULL) { 143 int token; 144 if (!*p) 145 continue; 146 147 token = match_token(p, tokens, args); 148 switch (token) { 149 case Opt_degraded: 150 printk(KERN_INFO "btrfs: allowing degraded mounts\n"); 151 btrfs_set_opt(info->mount_opt, DEGRADED); 152 break; 153 case Opt_subvol: 154 case Opt_device: 155 /* 156 * These are parsed by btrfs_parse_early_options 157 * and can be happily ignored here. 158 */ 159 break; 160 case Opt_nodatasum: 161 printk(KERN_INFO "btrfs: setting nodatasum\n"); 162 btrfs_set_opt(info->mount_opt, NODATASUM); 163 break; 164 case Opt_nodatacow: 165 printk(KERN_INFO "btrfs: setting nodatacow\n"); 166 btrfs_set_opt(info->mount_opt, NODATACOW); 167 btrfs_set_opt(info->mount_opt, NODATASUM); 168 break; 169 case Opt_compress: 170 printk(KERN_INFO "btrfs: use compression\n"); 171 btrfs_set_opt(info->mount_opt, COMPRESS); 172 break; 173 case Opt_ssd: 174 printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); 175 btrfs_set_opt(info->mount_opt, SSD); 176 break; 177 case Opt_ssd_spread: 178 printk(KERN_INFO "btrfs: use spread ssd " 179 "allocation scheme\n"); 180 btrfs_set_opt(info->mount_opt, SSD); 181 btrfs_set_opt(info->mount_opt, SSD_SPREAD); 182 break; 183 case Opt_nossd: 184 printk(KERN_INFO "btrfs: not using ssd allocation " 185 "scheme\n"); 186 btrfs_set_opt(info->mount_opt, NOSSD); 187 btrfs_clear_opt(info->mount_opt, SSD); 188 btrfs_clear_opt(info->mount_opt, SSD_SPREAD); 189 break; 190 case Opt_nobarrier: 191 printk(KERN_INFO "btrfs: turning off barriers\n"); 192 btrfs_set_opt(info->mount_opt, NOBARRIER); 193 break; 194 case Opt_thread_pool: 195 intarg = 0; 196 match_int(&args[0], &intarg); 197 if (intarg) { 198 info->thread_pool_size = intarg; 199 printk(KERN_INFO "btrfs: thread pool %d\n", 200 info->thread_pool_size); 201 } 202 break; 203 case Opt_max_extent: 204 num = match_strdup(&args[0]); 205 if (num) { 206 info->max_extent = btrfs_parse_size(num); 207 kfree(num); 208 209 info->max_extent = max_t(u64, 210 info->max_extent, root->sectorsize); 211 printk(KERN_INFO "btrfs: max_extent at %llu\n", 212 (unsigned long long)info->max_extent); 213 } 214 break; 215 case Opt_max_inline: 216 num = match_strdup(&args[0]); 217 if (num) { 218 info->max_inline = btrfs_parse_size(num); 219 kfree(num); 220 221 if (info->max_inline) { 222 info->max_inline = max_t(u64, 223 info->max_inline, 224 root->sectorsize); 225 } 226 printk(KERN_INFO "btrfs: max_inline at %llu\n", 227 (unsigned long long)info->max_inline); 228 } 229 break; 230 case Opt_alloc_start: 231 num = match_strdup(&args[0]); 232 if (num) { 233 info->alloc_start = btrfs_parse_size(num); 234 kfree(num); 235 printk(KERN_INFO 236 "btrfs: allocations start at %llu\n", 237 (unsigned long long)info->alloc_start); 238 } 239 break; 240 case Opt_noacl: 241 root->fs_info->sb->s_flags &= ~MS_POSIXACL; 242 break; 243 case Opt_notreelog: 244 printk(KERN_INFO "btrfs: disabling tree log\n"); 245 btrfs_set_opt(info->mount_opt, NOTREELOG); 246 break; 247 case Opt_flushoncommit: 248 printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); 249 btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); 250 break; 251 case Opt_ratio: 252 intarg = 0; 253 match_int(&args[0], &intarg); 254 if (intarg) { 255 info->metadata_ratio = intarg; 256 printk(KERN_INFO "btrfs: metadata ratio %d\n", 257 info->metadata_ratio); 258 } 259 break; 260 default: 261 break; 262 } 263 } 264 kfree(options); 265 return 0; 266 } 267 268 /* 269 * Parse mount options that are required early in the mount process. 270 * 271 * All other options will be parsed on much later in the mount process and 272 * only when we need to allocate a new super block. 273 */ 274 static int btrfs_parse_early_options(const char *options, fmode_t flags, 275 void *holder, char **subvol_name, 276 struct btrfs_fs_devices **fs_devices) 277 { 278 substring_t args[MAX_OPT_ARGS]; 279 char *opts, *p; 280 int error = 0; 281 282 if (!options) 283 goto out; 284 285 /* 286 * strsep changes the string, duplicate it because parse_options 287 * gets called twice 288 */ 289 opts = kstrdup(options, GFP_KERNEL); 290 if (!opts) 291 return -ENOMEM; 292 293 while ((p = strsep(&opts, ",")) != NULL) { 294 int token; 295 if (!*p) 296 continue; 297 298 token = match_token(p, tokens, args); 299 switch (token) { 300 case Opt_subvol: 301 *subvol_name = match_strdup(&args[0]); 302 break; 303 case Opt_device: 304 error = btrfs_scan_one_device(match_strdup(&args[0]), 305 flags, holder, fs_devices); 306 if (error) 307 goto out_free_opts; 308 break; 309 default: 310 break; 311 } 312 } 313 314 out_free_opts: 315 kfree(opts); 316 out: 317 /* 318 * If no subvolume name is specified we use the default one. Allocate 319 * a copy of the string "." here so that code later in the 320 * mount path doesn't care if it's the default volume or another one. 321 */ 322 if (!*subvol_name) { 323 *subvol_name = kstrdup(".", GFP_KERNEL); 324 if (!*subvol_name) 325 return -ENOMEM; 326 } 327 return error; 328 } 329 330 static int btrfs_fill_super(struct super_block *sb, 331 struct btrfs_fs_devices *fs_devices, 332 void *data, int silent) 333 { 334 struct inode *inode; 335 struct dentry *root_dentry; 336 struct btrfs_super_block *disk_super; 337 struct btrfs_root *tree_root; 338 struct btrfs_key key; 339 int err; 340 341 sb->s_maxbytes = MAX_LFS_FILESIZE; 342 sb->s_magic = BTRFS_SUPER_MAGIC; 343 sb->s_op = &btrfs_super_ops; 344 sb->s_export_op = &btrfs_export_ops; 345 sb->s_xattr = btrfs_xattr_handlers; 346 sb->s_time_gran = 1; 347 sb->s_flags |= MS_POSIXACL; 348 349 tree_root = open_ctree(sb, fs_devices, (char *)data); 350 351 if (IS_ERR(tree_root)) { 352 printk("btrfs: open_ctree failed\n"); 353 return PTR_ERR(tree_root); 354 } 355 sb->s_fs_info = tree_root; 356 disk_super = &tree_root->fs_info->super_copy; 357 358 key.objectid = BTRFS_FIRST_FREE_OBJECTID; 359 key.type = BTRFS_INODE_ITEM_KEY; 360 key.offset = 0; 361 inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root); 362 if (IS_ERR(inode)) { 363 err = PTR_ERR(inode); 364 goto fail_close; 365 } 366 367 root_dentry = d_alloc_root(inode); 368 if (!root_dentry) { 369 iput(inode); 370 err = -ENOMEM; 371 goto fail_close; 372 } 373 #if 0 374 /* this does the super kobj at the same time */ 375 err = btrfs_sysfs_add_super(tree_root->fs_info); 376 if (err) 377 goto fail_close; 378 #endif 379 380 sb->s_root = root_dentry; 381 382 save_mount_options(sb, data); 383 return 0; 384 385 fail_close: 386 close_ctree(tree_root); 387 return err; 388 } 389 390 int btrfs_sync_fs(struct super_block *sb, int wait) 391 { 392 struct btrfs_trans_handle *trans; 393 struct btrfs_root *root = btrfs_sb(sb); 394 int ret; 395 396 if (!wait) { 397 filemap_flush(root->fs_info->btree_inode->i_mapping); 398 return 0; 399 } 400 401 btrfs_start_delalloc_inodes(root); 402 btrfs_wait_ordered_extents(root, 0); 403 404 trans = btrfs_start_transaction(root, 1); 405 ret = btrfs_commit_transaction(trans, root); 406 return ret; 407 } 408 409 static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) 410 { 411 struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); 412 struct btrfs_fs_info *info = root->fs_info; 413 414 if (btrfs_test_opt(root, DEGRADED)) 415 seq_puts(seq, ",degraded"); 416 if (btrfs_test_opt(root, NODATASUM)) 417 seq_puts(seq, ",nodatasum"); 418 if (btrfs_test_opt(root, NODATACOW)) 419 seq_puts(seq, ",nodatacow"); 420 if (btrfs_test_opt(root, NOBARRIER)) 421 seq_puts(seq, ",nobarrier"); 422 if (info->max_extent != (u64)-1) 423 seq_printf(seq, ",max_extent=%llu", 424 (unsigned long long)info->max_extent); 425 if (info->max_inline != 8192 * 1024) 426 seq_printf(seq, ",max_inline=%llu", 427 (unsigned long long)info->max_inline); 428 if (info->alloc_start != 0) 429 seq_printf(seq, ",alloc_start=%llu", 430 (unsigned long long)info->alloc_start); 431 if (info->thread_pool_size != min_t(unsigned long, 432 num_online_cpus() + 2, 8)) 433 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); 434 if (btrfs_test_opt(root, COMPRESS)) 435 seq_puts(seq, ",compress"); 436 if (btrfs_test_opt(root, NOSSD)) 437 seq_puts(seq, ",nossd"); 438 if (btrfs_test_opt(root, SSD_SPREAD)) 439 seq_puts(seq, ",ssd_spread"); 440 else if (btrfs_test_opt(root, SSD)) 441 seq_puts(seq, ",ssd"); 442 if (btrfs_test_opt(root, NOTREELOG)) 443 seq_puts(seq, ",notreelog"); 444 if (btrfs_test_opt(root, FLUSHONCOMMIT)) 445 seq_puts(seq, ",flushoncommit"); 446 if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) 447 seq_puts(seq, ",noacl"); 448 return 0; 449 } 450 451 static int btrfs_test_super(struct super_block *s, void *data) 452 { 453 struct btrfs_fs_devices *test_fs_devices = data; 454 struct btrfs_root *root = btrfs_sb(s); 455 456 return root->fs_info->fs_devices == test_fs_devices; 457 } 458 459 /* 460 * Find a superblock for the given device / mount point. 461 * 462 * Note: This is based on get_sb_bdev from fs/super.c with a few additions 463 * for multiple device setup. Make sure to keep it in sync. 464 */ 465 static int btrfs_get_sb(struct file_system_type *fs_type, int flags, 466 const char *dev_name, void *data, struct vfsmount *mnt) 467 { 468 char *subvol_name = NULL; 469 struct block_device *bdev = NULL; 470 struct super_block *s; 471 struct dentry *root; 472 struct btrfs_fs_devices *fs_devices = NULL; 473 fmode_t mode = FMODE_READ; 474 int error = 0; 475 476 if (!(flags & MS_RDONLY)) 477 mode |= FMODE_WRITE; 478 479 error = btrfs_parse_early_options(data, mode, fs_type, 480 &subvol_name, &fs_devices); 481 if (error) 482 return error; 483 484 error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); 485 if (error) 486 goto error_free_subvol_name; 487 488 error = btrfs_open_devices(fs_devices, mode, fs_type); 489 if (error) 490 goto error_free_subvol_name; 491 492 if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { 493 error = -EACCES; 494 goto error_close_devices; 495 } 496 497 bdev = fs_devices->latest_bdev; 498 s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); 499 if (IS_ERR(s)) 500 goto error_s; 501 502 if (s->s_root) { 503 if ((flags ^ s->s_flags) & MS_RDONLY) { 504 deactivate_locked_super(s); 505 error = -EBUSY; 506 goto error_close_devices; 507 } 508 509 btrfs_close_devices(fs_devices); 510 } else { 511 char b[BDEVNAME_SIZE]; 512 513 s->s_flags = flags; 514 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); 515 error = btrfs_fill_super(s, fs_devices, data, 516 flags & MS_SILENT ? 1 : 0); 517 if (error) { 518 deactivate_locked_super(s); 519 goto error_free_subvol_name; 520 } 521 522 btrfs_sb(s)->fs_info->bdev_holder = fs_type; 523 s->s_flags |= MS_ACTIVE; 524 } 525 526 if (!strcmp(subvol_name, ".")) 527 root = dget(s->s_root); 528 else { 529 mutex_lock(&s->s_root->d_inode->i_mutex); 530 root = lookup_one_len(subvol_name, s->s_root, 531 strlen(subvol_name)); 532 mutex_unlock(&s->s_root->d_inode->i_mutex); 533 534 if (IS_ERR(root)) { 535 deactivate_locked_super(s); 536 error = PTR_ERR(root); 537 goto error_free_subvol_name; 538 } 539 if (!root->d_inode) { 540 dput(root); 541 deactivate_locked_super(s); 542 error = -ENXIO; 543 goto error_free_subvol_name; 544 } 545 } 546 547 mnt->mnt_sb = s; 548 mnt->mnt_root = root; 549 550 kfree(subvol_name); 551 return 0; 552 553 error_s: 554 error = PTR_ERR(s); 555 error_close_devices: 556 btrfs_close_devices(fs_devices); 557 error_free_subvol_name: 558 kfree(subvol_name); 559 return error; 560 } 561 562 static int btrfs_remount(struct super_block *sb, int *flags, char *data) 563 { 564 struct btrfs_root *root = btrfs_sb(sb); 565 int ret; 566 567 ret = btrfs_parse_options(root, data); 568 if (ret) 569 return -EINVAL; 570 571 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 572 return 0; 573 574 if (*flags & MS_RDONLY) { 575 sb->s_flags |= MS_RDONLY; 576 577 ret = btrfs_commit_super(root); 578 WARN_ON(ret); 579 } else { 580 if (root->fs_info->fs_devices->rw_devices == 0) 581 return -EACCES; 582 583 if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) 584 return -EINVAL; 585 586 /* recover relocation */ 587 ret = btrfs_recover_relocation(root); 588 WARN_ON(ret); 589 590 ret = btrfs_cleanup_fs_roots(root->fs_info); 591 WARN_ON(ret); 592 593 sb->s_flags &= ~MS_RDONLY; 594 } 595 596 return 0; 597 } 598 599 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) 600 { 601 struct btrfs_root *root = btrfs_sb(dentry->d_sb); 602 struct btrfs_super_block *disk_super = &root->fs_info->super_copy; 603 int bits = dentry->d_sb->s_blocksize_bits; 604 __be32 *fsid = (__be32 *)root->fs_info->fsid; 605 606 buf->f_namelen = BTRFS_NAME_LEN; 607 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; 608 buf->f_bfree = buf->f_blocks - 609 (btrfs_super_bytes_used(disk_super) >> bits); 610 buf->f_bavail = buf->f_bfree; 611 buf->f_bsize = dentry->d_sb->s_blocksize; 612 buf->f_type = BTRFS_SUPER_MAGIC; 613 614 /* We treat it as constant endianness (it doesn't matter _which_) 615 because we want the fsid to come out the same whether mounted 616 on a big-endian or little-endian host */ 617 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); 618 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); 619 /* Mask in the root object ID too, to disambiguate subvols */ 620 buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; 621 buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; 622 623 return 0; 624 } 625 626 static struct file_system_type btrfs_fs_type = { 627 .owner = THIS_MODULE, 628 .name = "btrfs", 629 .get_sb = btrfs_get_sb, 630 .kill_sb = kill_anon_super, 631 .fs_flags = FS_REQUIRES_DEV, 632 }; 633 634 /* 635 * used by btrfsctl to scan devices when no FS is mounted 636 */ 637 static long btrfs_control_ioctl(struct file *file, unsigned int cmd, 638 unsigned long arg) 639 { 640 struct btrfs_ioctl_vol_args *vol; 641 struct btrfs_fs_devices *fs_devices; 642 int ret = -ENOTTY; 643 644 if (!capable(CAP_SYS_ADMIN)) 645 return -EPERM; 646 647 vol = memdup_user((void __user *)arg, sizeof(*vol)); 648 if (IS_ERR(vol)) 649 return PTR_ERR(vol); 650 651 switch (cmd) { 652 case BTRFS_IOC_SCAN_DEV: 653 ret = btrfs_scan_one_device(vol->name, FMODE_READ, 654 &btrfs_fs_type, &fs_devices); 655 break; 656 } 657 658 kfree(vol); 659 return ret; 660 } 661 662 static int btrfs_freeze(struct super_block *sb) 663 { 664 struct btrfs_root *root = btrfs_sb(sb); 665 mutex_lock(&root->fs_info->transaction_kthread_mutex); 666 mutex_lock(&root->fs_info->cleaner_mutex); 667 return 0; 668 } 669 670 static int btrfs_unfreeze(struct super_block *sb) 671 { 672 struct btrfs_root *root = btrfs_sb(sb); 673 mutex_unlock(&root->fs_info->cleaner_mutex); 674 mutex_unlock(&root->fs_info->transaction_kthread_mutex); 675 return 0; 676 } 677 678 static struct super_operations btrfs_super_ops = { 679 .delete_inode = btrfs_delete_inode, 680 .put_super = btrfs_put_super, 681 .sync_fs = btrfs_sync_fs, 682 .show_options = btrfs_show_options, 683 .write_inode = btrfs_write_inode, 684 .dirty_inode = btrfs_dirty_inode, 685 .alloc_inode = btrfs_alloc_inode, 686 .destroy_inode = btrfs_destroy_inode, 687 .statfs = btrfs_statfs, 688 .remount_fs = btrfs_remount, 689 .freeze_fs = btrfs_freeze, 690 .unfreeze_fs = btrfs_unfreeze, 691 }; 692 693 static const struct file_operations btrfs_ctl_fops = { 694 .unlocked_ioctl = btrfs_control_ioctl, 695 .compat_ioctl = btrfs_control_ioctl, 696 .owner = THIS_MODULE, 697 }; 698 699 static struct miscdevice btrfs_misc = { 700 .minor = MISC_DYNAMIC_MINOR, 701 .name = "btrfs-control", 702 .fops = &btrfs_ctl_fops 703 }; 704 705 static int btrfs_interface_init(void) 706 { 707 return misc_register(&btrfs_misc); 708 } 709 710 static void btrfs_interface_exit(void) 711 { 712 if (misc_deregister(&btrfs_misc) < 0) 713 printk(KERN_INFO "misc_deregister failed for control device"); 714 } 715 716 static int __init init_btrfs_fs(void) 717 { 718 int err; 719 720 err = btrfs_init_sysfs(); 721 if (err) 722 return err; 723 724 err = btrfs_init_cachep(); 725 if (err) 726 goto free_sysfs; 727 728 err = extent_io_init(); 729 if (err) 730 goto free_cachep; 731 732 err = extent_map_init(); 733 if (err) 734 goto free_extent_io; 735 736 err = btrfs_interface_init(); 737 if (err) 738 goto free_extent_map; 739 740 err = register_filesystem(&btrfs_fs_type); 741 if (err) 742 goto unregister_ioctl; 743 744 printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); 745 return 0; 746 747 unregister_ioctl: 748 btrfs_interface_exit(); 749 free_extent_map: 750 extent_map_exit(); 751 free_extent_io: 752 extent_io_exit(); 753 free_cachep: 754 btrfs_destroy_cachep(); 755 free_sysfs: 756 btrfs_exit_sysfs(); 757 return err; 758 } 759 760 static void __exit exit_btrfs_fs(void) 761 { 762 btrfs_destroy_cachep(); 763 extent_map_exit(); 764 extent_io_exit(); 765 btrfs_interface_exit(); 766 unregister_filesystem(&btrfs_fs_type); 767 btrfs_exit_sysfs(); 768 btrfs_cleanup_fs_uuids(); 769 btrfs_zlib_exit(); 770 } 771 772 module_init(init_btrfs_fs) 773 module_exit(exit_btrfs_fs) 774 775 MODULE_LICENSE("GPL"); 776